This proposal is to complete the evaluation of a developmentally based, long-term, comprehensive intervention designed to prevent serious antisocial behavior and related adolescent problems. The project is being carried out at four sites (Durham, NC/Duke University;Nashville, TN/Vanderbilt University;rural Pennsylvania/Pennsylvania State University;and Seattle, WA/University of Washington). The screening procedure of Fast Track identified three successive cohorts of high-risk children in kindergarten by their early conduct problems at home and school. These children were randomly assigned by school to an intervention or control group. Intervention began in first grade with high-risk children, their adult caretakers, and their teachers based on a developmental model that specified six areas of risk and protective factors: parenting, child problem-solving and emotional coping skills, peer relations, classroom atmosphere, academic achievement, and home-school relations. It was continued in adolescence with an emphasis on protection from deviant peer influence;promoting positive identity, goals, and aspirations;and academic and vocational skill development. Analyses indicate the intervention has led to significant improvements in the hypothesized risk and protective factors and reductions in conduct problem behavior over the elementary school years. The primary aims of this proposal are: 1) to complete the assessments in the last 2 years of high school and the 2 years immediately after high school in order to evaluate intervention effects on mental health, crime, substance abuse, education and employment, and the use of community services;2) to determine whether characteristics of the participant sample moderated the effects of the intervention;3) to understand factors that mediate successful preventive intervention;4) to identify factors influencing participation and the relation between dosage and outcome;5) to continue to test the developmental model of early and late-starting conduct problems with the normative and high-risk samples;6) to continue to develop innovative methods for analyzing data from prevention trials;and 7) to provide data for an economic study of the impact of Fast Track on professional service utilization. The data collection plan calls for completion of annual parent and youth assessments at the end of 11th (cohort 3) and 12th grades (cohorts 2 and 3);a phone interview 1 year after the end of high school;and a face-to-face interview at age 20 that will provide a final assessment of mental health status, conduct problem behavior, substance use, educational progress, and employment status at the end of the teenage years (all cohorts).